Enhancing EV Charging Efficiency with Distributed ADMM-Based Approach for Minimizing Costs in EV Charging Stations

The decreasing costs of Battery Energy Storage Systems (BESS) and Renewable Energy (RE) technologies, such as Photovoltaics (PV) have made their integration into Electric Vehicle Charging Stations (EVCS) increasingly feasible. Nonetheless, in the absence of optimal power allocation strategies, excessive reliance on grid electricity may occur, leading to higher charging costs for EV users and reduced profitability for EVCS operators. To address this issue, this paper presents a framework based on the Alternating Direction Method of Multipliers (ADMM) for managing an integrated EVCS system incorporating both BESS and PV, with the objective of minimizing charging costs. The proposed method demonstrates the effectiveness of a decentralized control structure, achieving improved economic outcomes for EV users. In particular, the charging cost for EVs is reduced by approximately 3% when compared to a centralized approach. Furthermore, the study examines the influence of the penalty parameter in the ADMM algorithm, highlighting the critical role of appropriate parameter selection in achieving desirable convergence and performance.